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Metro Detroit Metalworking Club |
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PRESIDENT’S MESSAGE
First things first: I formally apologize to Emil or saying certain kinds
of engines are not heat engines – it turns out almost everything is.
The picture to the right that shows an engine made entirely of wood that
Joe Pietsch found started the discussion. According to the Wikipedia:
“A heat engine is a physical or theoretical device
that converts thermal
energy to mechanical output. The mechanical output is called work,
and the thermal energy input is called heat.
Heat engines typically run on a specific thermodynamic
cycle. Heat engines are often named after the thermodynamic cycle
they are modeled by. They often pick up alternate names, such as
gasoline/petrol, turbine, or steam engines. Heat engines can generate
heat inside the engine itself or it can absorb heat from an external
source. Heat engines can be open to the atmospheric air or sealed and
closed off to the outside (Open or closed cycle) .In engineering
and thermodynamics,
a heat engine performs the conversion of heat
energy
to mechanical
work by exploiting the temperature
gradient between a hot "source" and a cold "sink".
Heat is transferred
from the source, through the "working
body" of the engine, to the sink, and in this process some of
the heat is converted into work
by exploiting the properties of a working substance (usually a gas or
liquid).” So
Emil was right and I was wrong. I would feel bad about it except that
the study of thermodynamics looks fascinating. Rocket engines and
refrigerators (heat engines that are reversible) are heat engines. The
classifications are complex; some engines are not yet classified.
Working fluids can be gasses, liquids or even electrons. There are
thermal-acoustic engines. Some have no moving parts. Hurricanes,
tornadoes and storms are heat engines.
Next issue: I can’t make the
next meeting, I will be at the CNC Workshop in
MINUTES Meeting
was called to order at Two individuals, Ray Cavell of Joe Pietsch read parts of an article in Gas Engine Magazine of a working,
operational engine made entirely of wood.
Robust discussion of the technology required followed the reading. Bert Campbell demonstrated a home-built boring bar modified to cut balls
onto the end of a turning shaft. Ron Grimes demonstrated a rotary table from and announced his purchase of
the complete Sherline Products Miniature Machine Shop.
It was purchased at the North American Miniature Engineering
Society Show in Karl Gross demonstrated his appropriately named hit and miss engine,
developed from an article in a 1995 Home Shop Mechanics Magazine.
Mark Nowakowski presented a flysheet from Adam Hermann demonstrated a wick for an alcohol lamp made from cotton
bakery string, which he had found to be perfect for the application.
This is Bert
Campbell’s ball making attachment to his lathe. It mounts in his
quick-change tool post. The handle simple moves a boring head (which is
not modified and can be used as originally intended).
Karl Gross
showed his hit and miss engine in operation. It is called that because
the ignition is cut off when the engine exceeds a set speed. (It’s a
heat engine, I know that now, Emil).
Your president
has finally finished the CNC punch! This is a test piece, which was
punched in about 28 seconds at a rate of about 3 punches per second. Its
fun to watch.
No, I did not build a
coffin; it’s the shipping crate for sending the punch to the
Ron Grimes
showed us the rotary table that is part of his Sherline CNC setup.
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